Global MHD simulations of Saturns's magnetosphere at the time of Cassini approach

We present the results of a 3D global magnetohydrodynamic simulation of the magnetosphere of Saturn for the period of Cassini's initial approach and entry into the magnetosphere. We compare calculated bow shock and magnetopause locations with the Cassini measurements. In order to match the measured locations we use a substantial mass source due to the icy satellites (\sim1 x 10^{28} s^{-1} of water product ions). We find that the location of bow shock and magnetopause crossings are consistent with previous spacecraft measurements, although Cassini encountered the surfaces further from Saturn than the previously determined average location. In addition, we find that the shape of the model bow shock and magnetopause have smaller flaring angles than previous models and are asymmetric dawn-to-dusk. Finally, we find that tilt of Saturn's dipole and rotation axes results in asymmetries in the bow shock and magnetopause and in the magnetotail being hinged near Titan's orbit (\sim20 R _S)

Dual alpha2C/5HT1A receptor agonist allyphenyline induces gastroprotection and inhibits fundic and colonic contractility

Allyphenyline, a novel α2-adrenoceptor (AR) ligand, has been shown to selectively activate α2C-adrenoceptors (AR) and 5HT1A receptors, but also to behave as a neutral antagonist of α2A-ARs. We exploited this unique pharmacological profile to analyze the role of α2C-ARs and 5HT1A receptors in the regulation of gastric mucosal integrity and gastrointestinal motility

Effect of posterior pituitary denervation (PPD) on prolactin (PRL) and α-melanocyte-stimulating hormone (α-MSH) secretion of lactating rats

Previous data have clearly suggested that the posteriorpituitary (PP), consisting of neural lobe (NL) and intermediatelobe (IL), has a role in the control of anterior pituitaryPRL secretion. However, basic aspects of this regulatory mechanismlike (1), the role of an intact hypothalamic innervation ofthe PP as well as (2) the site of production of previously foundPRL releasing substance(s) have not yet been characterized.Denervation of the PP (PPD) is an effective method for having aselective lesion of the innervation of PP, indeed, PPD results ina disappearance of neurosecretory materials from NL and tyrosinehydroxylase (TH) immunoreactivity from IL, leaving bloodsupply of all three lobes intact. Blood samples were taken fromfreely moving sham and PP-denervated lactating rats before andafter 4-h separation from their pups and during the sucklingstimulus. PPD blocks separation-induced depletion but only attenuatessuckling induced release of PRL. Furthermore, it doublesplasma level of a-MSH during the entire sampling period,which has been used as a marker for in vivo secretory activityof IL cells. Lack of the separation-induced depression in plasmaPRL of PPD animals can be partially restored by normalizing thediabetes insipidus with treatment of a vasopressin analogue, 1-desamino-8-D-arginine-vasopressin (dDAVP). In contrast, d-DAVP, neither alone nor in combination with oxytocin (OXY), canchange PPD-induced elevation of plasma a-MSH as well as attenuationof PRL response induced by suckling. It is concludedthat: (1) contribution of the THDA system parallel to the confirmedrole in the regulation of a-MSH seems to be crucial forthe depletion of plasma PRL induced by separation but not forthe elevation due to suckling stimulus, (2) intact hypothalamicinnervations of both NL and IL, regulating water intake and thesecretion of a-MSH, respectively, are necessary for normal secretoryresponses of AL during lactation, (3) as well as for thepresence of PRF activity in PP, (4) which does not solely responsiblefor suckling-induced PRL release. Therefore, an interplaybetween several substances produced by NIL of the pituitarygland must have been responsible for the intactregulation of PRL secretion during lactation

Significant microsynteny with new evolutionary highlights is detected between Arabidopsis and legume model plants despite the lack of macrosynteny

The increased amount of data produced by large genome sequencing projects allows scientists to carry out important syntenic studies to a great extent. Detailed genetic maps and entirely or partially sequenced genomes are compared, and macro- and microsyntenic relations can be determined for different species. In our study, the syntenic relationships between key legume plants and two model plants, Arabidopsis thaliana and Populus trichocarpa were investigated. The comparison of the map position of 172 gene-based Medicago sativa markers to the organization of homologous A. thaliana genes could not identify any sign of macrosynteny between the two genomes. A 276 kb long section of chromosome 5 of the model legume Medicago truncatula was used to investigate potential microsynteny with the other legume Lotus japonicus, as well as with Arabidopsis and Populus. Besides the overall correlation found between the legume plants, the comparison revealed several microsyntenic regions in the two more distant plants with significant resemblance. Despite the large phylogenetic distance, clear microsyntenic regions between Medicago and Arabidopsis or Populus were detected unraveling new intragenomic evolutionary relations in Arabidopsis